Exploring the origins and history of food&drink around the world.

Posts Tagged ‘diet’

Participants at the Slav and Viking Festival in Wolin, Poland tend to be sticklers for authenticity. Many adorn their bodies with tattoos, and some adopt a Viking diet, slaughtering and roasting game.PHOTOGRAPH BY DAVID GUTTENFELDER, NATIONAL GEOGRAPHIC

Nationalgeographic.com

Historical interpreters bring a reconstructed longhouse to life at the Ribe Viking Center in Denmark. Meals were cooked over an open fire on a hearth, and Viking fare included salted herring, barley porridge, and boiled sheep heads.PHOTOGRAPH BY DAVID GUTTENFELDER, NATIONAL GEOGRAPHIC

By Catherine Zuckerman

All that marauding must have left the Vikings famished. It’s easy to envision a group of them around a table, ravenous after a long day of ransacking, devouring giant hunks of meat and hoisting horns-full of ale.
But that wouldn’t quite be fair, or accurate.
As tempting as it is to assume that Viking meals were crude and carnivorous, the truth is that everyday Viking fare included a range of foods that a health-minded modern person would applaud.
Picture, for example, that burly, bearded warrior throwing down his sword to enjoy a tart treat similar to yogurt, or refuel with a tangle of fresh greens.
“The Vikings had a wide range of food and wild herbs available to make tasty and nutritious dishes,” says Diana Bertelsen, who helped research and develop recipes for Denmark’s Ribe Viking Center—a reconstructed Viking settlement where visitors can immerse themselves in just about every aspect of Viking culture, including what and how they ate.
“There are no original recipes from the Viking age available,” says Bertelsen, but “we know for certain what crops and animals were available a thousand years ago. Excavations reveal what the Vikings ate and what they imported, for instance peaches and cinnamon.”

Of course a specific Viking’s diet was heavily influenced by his or her location, says medieval scholar Eleanor Rosamund Barraclough. In cold, dry, coastal Scandinavia, for example, fish such as herring and salmon provided a key source of protein and were typically dried and preserved in salt.
This “stockfish,” as it’s called, “is a bit like beef jerky, only fishy,” says Barraclough. “It would have been a valuable food source on long sea journeys.”
Wealth also played a part in determining one’s diet, says Barraclough. “In Greenland, Vikings ate more seals, particularly on the poorer farms, while on the richer farms they ate more caribou.”
Seasons, too, dictated a Viking’s daily provisions. Depending on the time of year, meals might include a wide variety of berries, turnips, cabbage and other greens—including seaweed—barley-based porridge, and flat bread made from rye. Dishes were typically simple, but “we have no reason to believe that the food was bland and tasteless,” says Bertelsen.
Indeed, archaeological evidence suggests that Viking cooks were fond of flavor-enhancing ingredients like onions, garlic, coriander, and dill.
Vikings also prepared special food to celebrate seasonal events. “Boars were said to be sacrificed during the winter Yule celebration, and solemn oaths taken on their bristles,” says Barraclough.
Dairy would have made a frequent appearance in many a Viking diet. The seafaring warriors were farmers, after all, and skilled at animal husbandry. Cows and sheep did provide meat, but they also gave the Vikings a reliable supply of buttermilk, cheese, butter, and other products.
In Iceland, especially, Vikings enjoyed their dairy, and often ate it in the form of skyr, a fermented, yogurt-like cheese that today is sometimes marketed as a dairy “superfood.” Viking lore mentions the creamy substance, says Barraclough, who recalls a “saga where a man hides from his enemies in a vat of skyr—which comes very specifically up to his nipples.”
Like much about the Vikings, their eating habits remain a source of fascination—and inspiration—for many people. In fact, given the Vikings’ physical strength and surprisingly healthy diet, it makes sense to wonder: Could the “Viking Diet” be the next “Paleo?”

Processing food before eating likely played key role in human evolution, study finds

How much time and effort do you spend chewing?

Although you probably enjoy a few leisurely meals every day, chances are that you spend very little time and muscular effort chewing your food. That kind of easy eating is very unusual. For perspective, our closest relatives, chimpanzees, spend almost half their day chewing, and with much greater force.

When and how did eating become so easy? And what were its consequences?

According to a new Harvard study, our ancestors between 2 and 3 million years ago started to spend far less time and effort chewing by adding meat to their diet and by using stone tools to process their food. The researchers estimate that such a diet would have saved early humans as many as 2.5 million chews per year, and made possible further changes that helped make us human. The study is described in a March 9 paper published in Nature.

One of the biggest puzzles in human evolution is how species such as Homo erectus evolved smaller teeth, smaller faces, and smaller guts, and yet managed to get more energy from food to pay for their bigger brains and bodies before cooking was invented. “What we showed is that…by processing food, especially meat, before eating it, humans not only decrease the effort needed to chew it, but also chew it much more effectively” said Katie Zink, the first author of the study, and a lecturer working in the lab of Daniel Lieberman, the Edwin M. Lerner II Professor of Biological Sciences.

By changing their diets to include just 33 percent meat, and processing their food – slicing meat and pounding vegetables – before eating, Zink and Lieberman found that the muscular effort required per chew and the number of chews required per day was reduced by almost 20 percent. They also found that by simply slicing meat with the sorts of simple tools available more than 2 million years ago, humans were able to swallow smaller, more easily digestible pieces than would have been possible without using tools.

“Eating meat and using stone tools to process food apparently made possible key reductions in the jaws, teeth and chewing muscles that occurred during human evolution,” Zink said.

But testing a process as basic as chewing isn’t as easy – or as attractive – as it might sound.

“What Katie did was creative but sometimes, frankly, a little stomach-churning,” Lieberman said. “Not only did she have people come into the lab, chew raw meat and other foods, and spit them out, but then she had to analyze the stuff.”

It wasn’t just any food – or any meat – that subjects noshed on.

To approximate the toughness and texture of the game that early humans ate, Zink and Lieberman (after much experimentation) settled on using goat – which subjects chewed raw while Zink used instruments attached to their jaw to measure the effort involved.

In each trial, volunteers were given, in random order, a selection of foods prepared in several ways – raw, sliced, pounded and cooked goat, as well as several vegetables, including carrots, beets and yams. After chewing each morsel until they would normally swallow, subjects spit out the food. Zink then spread the individual food particles out onto a tray, photographed them, and digitally measured their sizes.

“What we found was that humans cannot eat raw meat effectively with their low-crested teeth. When you give people raw goat, they chew and chew and chew, and most of the goat is still one big clump – it’s like chewing gum,” Lieberman said. “But once you start processing it mechanically, even just slicing it, the effects on chewing performance are dramatic.”

But why study chewing at all?

“Chewing is one of the key characteristics of being a mammal,” Lieberman explained. “Most other animals, like reptiles, barely chew their food — they just swallow it whole. The evolution of the ability to chew food into smaller particles gave mammals a big boost of extra energy because smaller particles have a higher surface area to volume ratio, allowing digestive enzymes to then break food down more efficiently.”

Most mammals, however, eat a relatively low-quality diet- think of cows eating grass and hay – that they need to spend most of the day chewing. Even humans’ closest ape relatives, with a diet that consists mainly of fruit, must spend nearly half their day chewing to extract enough energy from their food, Lieberman said.

“But we humans have done something really remarkable,” he said. “We eat even higher-quality foods than chimpanzees, and spend an order of magnitude less time chewing them.”

Making that change, however, presented early humans with a new challenge.

One of the critical components of that higher-quality diet is meat, which – despite being calorically dense – is very difficult for humans to chew effectively.

“Meat has a lot of nutrients, but it is also very elastic. You can think of it as being like a rubber band,” Zink said. “So the problem is that we can’t break it down with our flat, low-cusped teeth. But if you slice it up, then you do not need to use your teeth to break it down as much, and you swallow much smaller particles. Cooking makes chewing even easier.”

That pre-processing, and the reductions in chewing effort that came with it, Zink and Lieberman said, may have opened the door to one of the most important lifestyle changes in human evolution – the emergence of hunting and gathering.

“With the origin of the genus Homo…we went from having snouts and big teeth and large chewing muscles to having smaller teeth, smaller chewing muscles, and snoutless faces” Lieberman said. “Those changes, and others, allowed for selection for speech and other shifts in the head, like bigger brains. Underlying that, to some extent, is the simplest technology of all: slicing meat into smaller pieces, and pounding vegetables before you chew them.”

The impact that higher-quality diets and easier chewing could have on early humans is clear if you imagine what day-to-day life might have been like millions of years ago.

“Suppose you go out hunting for antelopes like impala or kudu, but at the end of the day you come back empty-handed, which happened fairly often for early humans,” Lieberman said. “Chimps couldn’t survive that way – they would then have to spend all night eating.

“Following the invention of hunting and gathering, though, humans can benefit from a division of labor,” he continued. “Someone else may have come back with an impala, or some tubers you could eat. And instead of spending all night eating it, you’d spend a lot less time, energy and effort to chew it by pounding it or cutting it with just a few stone stone tools. What a dramatic shift!”

Though many aspects of our biology changed when the genus Homo evolved, Zink and Lieberman said that processing food before eating almost surely played a significant role.

“One of the innovations that helped make us human is cutting up and pounding our food,” Lieberman said. “Extra-oral processing first by using stone tools and then by cooking played a very important role in human evolution because it released selection for big faces and big teeth, which then enabled selection for shorter faces which were important for speech, and enabled us to grow big brains and have large bodies. We are partly who we are because we chew less.”

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The Batwa hunter-gatherers collect and roast wild yams in the Bwindi Impenetrable Forest in Uganda.

The difference between humans and their closest relatives is partly a matter of taste. Yams, pumpkins, and squash are as bland as potatoes to our tongues today, but to a chimp and our ancestors, wild varieties were bitter and yucky. Now scientists have pinpointed some of the genetic changes that allowed our ancestors to diversify their palates, potentially allowing them to take better advantage of a wide range of foods—and conquer the world.

As humans adapted to new habitats, they had to become open to new culinary experiences. They ate more starchy tuberous roots, learned to cook their meat and bitter root vegetables, and eventually domesticated plants and animals. Those dietary revolutions helped make us human, giving our bodies the extra calories that enlarged our brains, while allowing our guts, jaws, and teeth to shrink as we ate softer, more easily digestible food.

To figure out how these changes evolved, anthropological geneticist George Perry of Pennsylvania State University, University Park, and his colleagues compared the genomes of modern humans and chimpanzees to the newly published genomes of a Neandertal and one of its close relatives, a mysterious human ancestor known as a Denisovan, known only from a few bones found in a Russian cave. All three groups of humans had lost two bitter taste genes, TAS2R62 and TAS2R64, that are still present in chimpanzees, the team reports this month in the Journal of Human Evolution.

Two million years ago, our early ancestors such as Australopithecus or early members of Homo likely found wild yams and other tubers bitter. But as humans began to cook, they could roast tuberous root vegetables long enough that they weren’t as bitter. (Today, hunter-gatherers still rely on roasted tubers as a major source of calories.) At the same time, hominins—members of the human family—lost those two particular bitter taste genes, so they were presumably able to eat a wider range of tuberous plants. Modern humans, Neandertals, and Denisovans all lost the ability to detect the bitter flavor in some wild plants and eventually modern humans bred varieties of squashes, gourds, and yams that are less bitter than the wild types.

The team also found some intriguing differences between modern humans, who arose in Africa in the past 200,000 years or so, and our archaic human relatives, such as Neandertals and Denisovans. Our lineage, for example, carries an average of six copies, and as many as 20 copies, of the salivary amylase gene, AMY1. The gene produces the enzyme amylase in our saliva, which has been thought to help digest sugars in starchy foods, although its role in human digestion is still unproven. By contrast, chimps, Neandertals, and Denisovans carry only one to two copies of the salivary amylase gene, which suggests they got fewer calories from starchy veggies than modern humans. This confirms an earlier finding that Neandertals didn’t have extra copies of the amylase gene and is “definitely a surprise,” says biological anthropologist Richard Wrangham of Harvard University, who was not a co-author on this paper.

Wrangham has proposed that a key human ancestor, H. erectus, relied on cooking starchy tuberous roots to get enough calories to expand its brain. But if so, that distant ancestor wasn’t using extra copies of the amylase gene to extract more calories from these plant foods. He and Harvard postdoctoral researcher Rachel Carmody suggest the amylase copies may have had other functions, such as helping prevent cavities.

And although researchers have proposed earlier that this adaptation took place with the invention of agriculture, Perry and his colleagues have found that hunter-gatherers also carry the extra copies of the salivary amylase gene. This suggests that this adaptation took place in modern humans, after the split with the ancestor they shared with Neandertals about 600,000 years ago but before plants were domesticated 10,000 years ago. “This doesn’t mean that earlier hominins weren’t eating more starch, but perhaps they weren’t getting all of the same benefits as modern humans,” Perry says.

One sign that cooking shaped our ancestors’ genomes as well as our guts is that humans, Neandertals, and Denisovans all have lost a masticatory myosin gene, MYH16, that helps build strong chewing muscles in the jaws of chimps. This may be one result of learning to cook, which softens food, Perry says. This fits with evidence that some early hominins were chefs—Neandertals in the Middle East cooked barley porridge, for example.

Now, Perry and his colleagues are trying to figure out when this gene was lost in the human lineage. The loss of the gene for muscular jaws in Neandertals, Denisovans, and moderns suggests that cooking arose in their common ancestor, H. erectus, he says.

health care system? Politicians and others continue to debate this issue. They always conclude that more money is the answer. But this approach is doomed to failure. How can it work when it’s taken 40,000 years for humans to get into such horrible shape?

How did it happen? And is there a solution?

Dr. Barry Bogin is a professor of anthropology at the University of Michigan. He says we all envision our Paleolithic ancestors as being short, bent-over people with small brains, but actually, they were a tad taller and with brains as large as ours. And if alive today, they would not require hospitalization for so much degenerative disease.

Admittedly, most stone-age people did not live as long as today’s North Americans. Large numbers died while hunting animals or from infection due to lack of antibiotics. Others suffered terrible deaths from childbirth.

But the ones that escaped these problems did not face cardiovascular disease, diabetes, hypertension, or obesity—all of today’s big killers—later in life.

What protected them? Ironically, it was the things they lacked that saved them. Three meals a day were never guaranteed, so they had to continually exert themselves to find food.

Dr. Bogin reports that today most people expend only 400 calories to complete the day’s chores. Cars, television sets, and computers don’t burn up calories.

Stone-age people lost 1,600 calories by hunting and gathering food. This, along with the absence of fast-food outlets and supermarkets, kept them thin, a major factor in preventing degenerative disease.

Nutritional anthropologists can pinpoint what stone-age people ate—and how their nutrition safeguarded them from certain diseases—by analyzing their bones and fossilized human waste.

Sugar and Salt

Possibly, their major protection was the lack of sugar. The only source of pure sugar was honey, which was not easy to get and only available in certain areas a few months of the year.

Today, we consume 20 teaspoons of sugar daily, which translates into 146,000 calories a year and 42 pounds of body fat if it’s not burned up by exercise.

What’s beyond belief is that Americans now eat more refined sugar in a single day than stone-age people ate in a lifetime! This is one reason why stone-age people were free of cavities.

Stone-age people also lacked excessive sodium. They consumed about 1,000 milligrams of sodium daily. Today, we use from 4,000 to 6,000 milligrams every day, mostly from supermarket foods. This is one reason why hypertension is a leading cause of death.

Fiber vs. Saturated Fat

Paleolithic men had phenomenal good luck. They consumed up to 150 grams of fiber daily due to a diet rich in plant food. This triggered large soft stools and prevented constipation, diverticulitis, and possibly colon cancer. North Americans consume a mere 15 grams of fiber daily.

Dr. Bogin says they were also not exposed to saturated fats, the type linked to coronary disease. It’s estimated that the American public devours 200 hamburgers every second.

Paleolithic people didn’t eat significant amounts of saturated fat even in areas where game was abundant. The bison, which roamed the prairies, were thin, and what fat they contained was largely unsaturated fat. In fact, Dr. Bogin claims some of their fat consisted of omega-3 fatty acids, the kind found in fish.

Nor could thirsty stone-age people run to the corner store for a 10-ounce can of soda loaded with 8 teaspoons of sugar. Neither had they learned to ferment grains and grapes. Without alcohol, they escaped some cancers. All they had was calorie-free water, no doubt cleaner than today’s drinking water.

Paleolithic people also escaped osteoporosis. This, in spite of the fact that cows and goats were not herded for dairy products. But their plant foods were so high in calcium that they averaged 1,900 milligrams of calcium a day.

We can learn from our ancient ancestors by eating whole-wheat bread and bran cereals, adding more fruit and vegetables to our diet, drinking milk, and above all, saying no to drinks laden with sugar. And if we rise out of our chairs more often, maybe then we could control the escalating costs in health care.

By Gifford-Jones, M.D., He is a medical journalist based in Toronto. His website is DocGiff.com. He may be contacted at Info@docgiff.com.

CHICAGO, ILLINOIS—In Pompeii, a team led by University of Cincinnati archaeologist Steven Ellis has discovered evidence that challenges the traditional perception of Roman dining, which holds that the rich feasted on exotic animals while the poor were reduced to eating simple fare. In a two block area near the city's Porta Stabia gate, the team excavated some 20 shop fronts that would have served food and drink to the general public. Scraps of food recovered from latrines and cesspits show that these businesses weren't just serving gruel, but a wide variety of foods, including cuts of expensive meat and salted fish imported from Spain. In one drain the archaeologists found shellfish and a leg joint of a giraffe, the first giraffe bone to be reported at a site in Italy. "The traditional vision of some mass of hapless lemmings—scrounging for whatever they can pinch from the side of a street, or huddled around a bowl of gruel—needs to be replaced by a higher fare and standard of living, at least for the urbanites in Pompeii," said Ellis.archaeology.org
Jan 2, 2014

More information on this topic:
No scrounging for scraps: Research uncovers the diets of the middle and lower class in Pompeii

University of Cincinnati archaeologists are turning up discoveries in the famed Roman city of Pompeii that are wiping out the historic perceptions of how the Romans dined, with the rich enjoying delicacies such as flamingos and the poor scrounging for soup or gruel. Steven Ellis, a University of Cincinnati associate professor of classics, will present these discoveries on Jan. 4, at the joint annual meeting of the Archaeological Institute of America (AIA) and American Philological Association (APA) in Chicago.

UC teams of archaeologists have spent more than a decade at two city blocks within a non-elite district in the Roman city of Pompeii, which was buried under a volcano in 79 AD. The excavations are uncovering the earlier use of buildings that would have dated back to the 6th century.

Ellis says the excavation is producing a complete archaeological analysis of homes, shops and businesses at a forgotten area inside one of the busiest gates of Pompeii, the Porta Stabia.

The area covers 10 separate building plots and a total of 20 shop fronts, most of which served food and drink. The waste that was examined included collections from drains as well as 10 latrines and cesspits, which yielded mineralized and charred food waste coming from kitchens and excrement. Ellis says among the discoveries in the drains was an abundance of the remains of fully-processed foods, especially grains.
“The material from the drains revealed a range and quantity of materials to suggest a rather clear socio-economic distinction between the activities and consumption habits of each property, which were otherwise indistinguishable hospitality businesses,” says Ellis. Findings revealed foods that would have been inexpensive and widely available, such as grains, fruits, nuts, olives, lentils, local fish and chicken eggs, as well as minimal cuts of more expensive meat and salted fish from Spain. Waste from neighboring drains would also turn up less of a variety of foods, revealing a socioeconomic distinction between neighbors.

A drain from a central property revealed a richer variety of foods as well as imports from outside Italy, such as shellfish, sea urchin and even delicacies including the butchered leg joint of a giraffe. “That the bone represents the height of exotic food is underscored by the fact that this is thought to be the only giraffe bone ever recorded from an archaeological excavation in Roman Italy,” says Ellis. “How part of the animal, butchered, came to be a kitchen scrap in a seemingly standard Pompeian restaurant not only speaks to long-distance trade in exotic and wild animals, but also something of the richness, variety and range of a non-elite diet.”

Deposits also included exotic and imported spices, some from as far away as Indonesia.

Ellis adds that one of the deposits dates as far back as the 4th century, which he says is a particularly valuable discovery, since few other ritual deposits survived from that early stage in the development of Pompeii.

“The ultimate aim of our research is to reveal the structural and social relationships over time between working-class Pompeian households, as well as to determine the role that sub-elites played in the shaping of the city, and to register their response to city-and Mediterranean-wide historical, political and economic developments. However, one of the larger datasets and themes of our research has been diet and the infrastructure of food consumption and food ways,” says Ellis.

He adds that as a result of the discoveries, “The traditional vision of some mass of hapless lemmings – scrounging for whatever they can pinch from the side of a street, or huddled around a bowl of gruel – needs to be replaced by a higher fare and standard of living, at least for the urbanites in Pompeii.”

Contributing team leaders on the project who have focused on diet and food ways are Michael MacKinnon, a professor the University of Winnipeg; Mark Robinson, professor at Oxford University; Jennifer Robinson, also of Oxford University; Emily Holt, professor at Oberlin College and Professor Andrew Fairbairn of the University of Queensland.

We are not biologically identical to our Paleolithic predecessors, nor do we have access to the foods they ate. And deducing dietary guidelines from modern foraging societies is difficult because they vary so much by geography, season and opportunity

Meet Grok. According to his online profile, he is a tall, lean, ripped and agile 30-year-old. By every measure, Grok is in superb health: low blood pressure; no inflammation; ideal levels of insulin, glucose, cholesterol and triglycerides. He and his family eat really healthy, too. They gather wild seeds, grasses, and nuts; seasonal vegetables; roots and berries. They hunt and fish their own meat. Between foraging, building sturdy shelters from natural materials, collecting firewood and fending off dangerous predators far larger than himself, Grok’s life is strenuous, perilous and physically demanding. Yet, somehow, he is a stress-free dude who always manages to get enough sleep and finds the time to enjoy moments of tranquility beside gurgling creeks. He is perfectly suited to his environment in every way. He is totally Zen.

Ostensibly, Grok is “a rather typical hunter–gatherer” living before the dawn of agriculture—an “official primal prototype.” He is the poster-persona for fitness author and blogger Mark Sisson’s “Primal Blueprint”—a set of guidelines that “allows you to control how your genes express themselves in order to build the strongest, leanest, healthiest body possible, taking clues from evolutionary biology (that’s the primal part).” These guidelines incorporate many principles of what is more commonly known as the Paleolithic, or caveman, diet, which started to whet people’s appetites as early as the 1960s and is available in many different flavors today.

Proponents of the Paleo diet follow a nutritional plan based on the eating habits of our ancestors in the Paleolithic period, between 2.5 million and 10,000 years ago. Before agriculture and industry, humans presumably lived as hunter–gatherers: picking berry after berry off of bushes; digging up tumescent tubers; chasing mammals to the point of exhaustion; scavenging meat, fat and organs from animals that larger predators had killed; and eventually learning to fish with lines and hooks and hunt with spears, nets, bows and arrows.

Most Paleo dieters of today do none of this, with the exception of occasional hunting trips or a little urban foraging. Instead, their diet is largely defined by what they do not do: most do not eat dairy or processed grains of any kind, because humans did not invent such foods until after the Paleolithic; peanuts, lentils, beans, peas and other legumes are off the menu, but nuts are okay; meat is consumed in large quantities, often cooked in animal fat of some kind; Paleo dieters sometimes eat fruit and often devour vegetables; and processed sugars are prohibited, but a little honey now and then is fine.

Almost equal numbers of advocates and critics seem to have gathered at the Paleo diet dinner table and both tribes have a few particularly vociferous members. Critiques of the Paleo diet range from the mild—Eh, it’s certainly not the worst way to eat—to the acerbic: It is nonsensical and sometimes dangerously restrictive. Most recently, in her book Paleofantasy, evolutionary biologist Marlene Zuk of the University of California, Riverside, debunks what she identifies as myths central to the Paleo diet and the larger Paleo lifestyle movement.

Most nutritionists consent that the Paleo diet gets at least one thing right—cutting down on processed foods that have been highly modified from their raw state through various methods of preservation. Examples include white bread and other refined flour products, artificial cheese, certain cold cuts and packaged meats, potato chips, and sugary cereals. Such processed foods often offer less protein, fiber and iron than their unprocessed equivalents, and some are packed with sodium and preservatives that may increase the risk of heart disease and certain cancers.

But the Paleo diet bans more than just highly processed junk foods—in its most traditional form, it prohibits any kind of food unavailable to stone age hunter–gatherers, including dairy rich in calcium, grains replete with fiber, and vitamins and legumes packed with protein. The rationale for such constraint—in fact the entire premise of the Paleo diet—is, at best, only half correct. Because the human body adapted to life in the stone age, Paleo dieters argue—and because our genetics and anatomy have changed very little since then, they say—we should emulate the diets of our Paleo predecessors as closely as possible in order to be healthy. Obesity, heart disease, diabetes, cancer and many other “modern” diseases, the reasoning goes, result primarily from the incompatibility of our stone age anatomy with our contemporary way of eating.

Diet has been an important part of our evolution—as it is for every species—and we have inherited many adaptations from our Paleo predecessors. Understanding how we evolved could, in principle, help us make smarter dietary choices today. But the logic behind the Paleo diet fails in several ways: by making apotheosis of one particular slice of our evolutionary history; by insisting that we are biologically identical to stone age humans; and by denying the benefits of some of our more modern methods of eating.

“‘Paleofantasies’ call to mind a time when everything about us—body, mind, and behavior—was in sync with the environment…but no such time existed,” Zuk wrote in her book. “We and every other living thing have always lurched along in evolutionary time, with the inevitable trade-offs that are a hallmark of life.”

On his website, Sisson writes that “while the world has changed in innumerable ways in the last 10,000 years (for better and worse), the human genome has changed very little and thus only thrives under similar conditions.” This is simply not true. In fact, this reasoning misconstrues how evolution works. If humans and other organisms could only thrive in circumstances similar to the ones their predecessors lived in, life would not have lasted very long.

Several examples of recent and relatively speedy human evolution underscore that our anatomy and genetics have not been set in stone since the stone age. Within a span of 7,000 years, for instance, people adapted to eating dairy by developing lactose tolerance. Usually, the gene encoding an enzyme named lactase—which breaks down lactose sugars in milk—shuts down after infancy; when dairy became prevalent, many people evolved a mutation that kept the gene turned on throughout life. Likewise, the genetic mutation responsible for blue eyes likely arose between 6,000 and 10,000 years ago. And in regions where malaria is common, natural selection has modified people’s immune systems and red blood cells in ways that help them resist the mosquito-borne disease; some of these genetic mutations appeared within the last 10,000 or even 5,000 years. The organisms with which we share our bodies have evolved even faster, particularly the billions of bacteria living in our intestines. Our gut bacteria interact with our food in many ways, helping us break down tough plant fibers, but also competing for calories. We do not have direct evidence of which bacterial species thrived in Paleolithic intestines, but we can be sure that their microbial communities do not exactly match our own.

Even if eating only foods available to hunter–gatherers in the Paleolithic made sense, it would be impossible. As Christina Warinner of the University of Zurich emphasizes in her 2012 TED talk, just about every single species commonly consumed today—whether a fruit, vegetable or animal—is drastically different from its Paleolithic predecessor. In most cases, we have transformed the species we eat through artificial selection: we have bred cows, chickens and goats to provide as much meat, milk and eggs as possible and have sown seeds only from plants with the most desirable traits—with the biggest fruits, plumpest kernels, sweetest flesh and fewest natural toxins. Cabbage, broccoli, cauliflower, Brussels sprouts and kale are all different cultivars of a single species, Brassica oleracea; generation by generation, we reshaped this one plant’s leaves, stems and flowers into wildly different arrangements, the same way we bred Welsh corgis, pugs, dachshunds, Saint Bernards and greyhounds out of a single wolf species. Corn was once a straggly grass known as teosinte and tomatoes were once much smaller berries. And the wild ancestors of bananas were rife with seeds.

The Paleo diet not only misunderstands how our own species, the organisms inside our bodies and the animals and plants we eat have evolved over the last 10,000 years, it also ignores much of the evidence about our ancestors’ health during their—often brief—individual life spans (even if a minority of our Paleo ancestors made it into their 40s or beyond, many children likely died before age 15). In contrast to Grok, neither Paleo hunter–gatherers nor our more recent predecessors were sculpted Adonises immune to all disease. A recent study in The Lancet looked for signs of atherosclerosis—arteries clogged with cholesterol and fats—in more than one hundred ancient mummies from societies of farmers, foragers and hunter–gatherers around the world, including Egypt, Peru, the southwestern U.S and the Aleutian Islands. “A common assumption is that atherosclerosis is predominately lifestyle-related, and that if modern human beings could emulate preindustrial or even preagricultural lifestyles, that atherosclerosis, or least its clinical manifestations, would be avoided,” the researchers wrote. But they found evidence of probable or definite atherosclerosis in 47 of 137 mummies from each of the different geographical regions. And even if heart disease, cancer, obesity and diabetes were not as common among our predecessors, they still faced numerous threats to their health that modern sanitation and medicine have rendered negligible for people in industrialized nations, such as infestations of parasites and certain lethal bacterial and viral infections.

Some Paleo dieters emphasize that they never believed in one true caveman lifestyle or diet and that—in the fashion of Sisson’s Blueprint—they use our evolutionary past to form guidelines, not scripture. That strategy seems reasonably solid at first, but quickly disintegrates. Even though researchers know enough to make some generalizations about human diets in the Paleolithic with reasonable certainty, the details remain murky. Exactly what proportions of meat and vegetables did different hominid species eat in the Paleolithic? It’s not clear. Just how far back were our ancestors eating grains and dairy? Perhaps far earlier than we initially thought. What we can say for certain is that in the Paleolithic, the human diet varied immensely by geography, season and opportunity. “We now know that humans have evolved not to subsist on a single, Paleolithic diet but to be flexible eaters, an insight that has important implications for the current debate over what people today should eat in order to be healthy,” anthropologist William Leonard of Northwestern University wrote in Scientific American in 2002.
We cannot time travel and join our Paleo ancestors by the campfire as they prepare to eat; likewise, shards of ancient pottery and fossilized teeth can tell us only so much. If we compare the diets of so-called modern hunter-gatherers, however, we see just how difficult it is to find meaningful commonalities and extract useful dietary guidelines from their disparate lives (see infographic). Which hunter–gatherer tribe are we supposed to mimic, exactly? How do we reconcile the Inuit diet—mostly the flesh of sea mammals—with the more varied plant and land animal diet of the Hadza or !Kung? Chucking the many different hunter–gather diets into a blender to come up with some kind of quintessential smoothie is a little ridiculous. “Too often modern health problems are portrayed as the result of eating ‘bad’ foods that are departures from the natural human diet…This is a fundamentally flawed approach to assessing human nutritional needs,” Leonard wrote. “Our species was not designed to subsist on a single, optimal diet. What is remarkable about human beings is the extraordinary variety of what we eat. We have been able to thrive in almost every ecosystem on the Earth, consuming diets ranging from almost all animal foods among populations of the Arctic to primarily tubers and cereal grains among populations in the high Andes.”

Closely examining one group of modern hunter–gatherers—the Hiwi—reveals how much variation exists within the diet of a single small foraging society and deflates the notion that hunter–gatherers have impeccable health. Such examination also makes obvious the immense gap between a genuine community of foragers and Paleo dieters living in modern cities, selectively shopping at farmers’ markets and making sure the dressing on their house salad is gluten, sugar and dairy free.

By latest count, about 800 Hiwi live in palm thatched huts in Colombia and Venezuela. In 1990 Ana Magdalena Hurtado and Kim Hill—now both at Arizona State University in Tempe—published a thorough study (pdf) of the Hiwi diet in the neotropical savannas of the Orinoco River basin in Southwestern Venezuela. Vast grasslands with belts of forest, these savannas receive plenty of rain between May and November. From January through March, however, precipitation is rare: the grasses shrivel, while lakes and lagoons evaporate. Fish trapped in shrinking pools of water are easy targets for caiman, capybaras and turtles. In turn, the desiccating lakes become prime hunting territory for the Hiwi. During the wet season, however, the Hiwi mainly hunt for animals in the forest, using bows and arrows.

The Hiwi gather and hunt a diverse group of plants and animals from the savannas, forests, rivers and swamps. Their main sources of meat are capybara, collared peccary, deer, anteater, armadillo, and feral cattle, numerous species of fish, and at least some turtle species. Less commonly consumed animals include iguanas and savanna lizards, wild rabbits, and many birds. Not exactly the kind of meat Paleo dieters and others in urban areas can easily obtain.

Five roots, both bitter and sweet, are staples in the Hiwi diet, as are palm nuts and palm hearts, several different fruits, a wild legume named Campsiandra comosa, and honey produced by several bee species and sometimes by wasps. A few Hiwi families tend small, scattered and largely unproductive fields of plantains, corn and squash. At neighboring cattle ranches in a town about 30 kilometers away, some Hiwi buy rice, noodles, corn flour and sugar. Anthropologists and tourists have also given the Hiwi similar processed foods as gifts (see illustration at top).

Hill and Hurtado calculated that foods hunted and collected in the wild account for 95 percent of the Hiwi’s total caloric intake; the remaining 5 percent comes from store-bought goods as well as from fruits and squash gathered from the Hiwi’s small fields. They rely more on purchased goods during the peak of the dry season.

The Hiwi are not particularly healthy. Compared to the Ache, a hunter–gatherer tribe in Paraguay, the Hiwi are shorter, thinner, more lethargic and less well nourished. Hiwi men and women of all ages constantly complain of hunger. Many Hiwi are heavily infected with parasitic hookworms, which burrow into the small intestine and feed on blood. And only 50 percent of Hiwi children survive beyond the age of 15.

Drop Grok into the Hiwi’s midst—or indeed among any modern or ancient hunter–gather society—and he would be a complete aberration. Grok cannot teach us how to live or eat; he never existed. Living off the land or restricting oneself to foods available before agriculture and industry does not guarantee good health. The human body is not simply a collection of adaptations to life in the Paleolithic—its legacy is far greater. Each of us is a dynamic assemblage of inherited traits that have been tweaked, transformed, lost and regained since the beginning of life itself. Such changes have not ceased in the past 10,000 years.

Ultimately—regardless of one’s intentions—the Paleo diet is founded more on privilege than on logic. Hunter–gatherers in the Paleolithic hunted and gathered because they had to. Paleo dieters attempt to eat like hunter–gatherers because they want to.

Australopithecus afarensis (pictured in an artist’s impression) had different diets from their ancestors

Topic Ancient diet

A new analysis of early human teeth from extinct fossils has found that they expanded their diets about 3.5 million years ago to include grasses and possibly animals.

Human ancestors’ diet changed 3.5 million years ago

A new analysis of early human teeth from extinct fossils has found that they expanded their diets about 3.5 million years ago to include grasses and possibly animals.

Before this, humanlike creatures – or hominins – ate a forest-based diet similar to modern gorillas and chimps.

Researchers analysed fossilised tooth enamel of 11 species of hominins and other primates found in East Africa.

The findings appear in four papers published in PNAS journal.

Like chimpanzees today, many of our early human ancestors lived in forests and ate a diet of leaves and fruits from trees, shrubs and herbs.

But scientists have now found that this changed 3.5 million years ago in the species Australopithecus afarensis and Kenyanthropus platyops.

Their diet included grasses, sedges, and possibly animals that ate such plants. They also tended to live in the open savannahs of Africa.

The new studies show that they not only lived there, but began to consume progressively more foods from the savannahs.

Researchers looked at samples from 175 hominins of 11 species, ranging from 1.4 to 4.1 million years old.

Their diet was analysed from the chemical make up of their teeth, identifying the carbon isotopes within them.

The ratios of different types of carbon atoms, or isotopes, in fossils can give clues to what a fossil creature ate because different foods have different carbon isotope signatures.

“What we have is chemical information on what our ancestors ate, which in simpler terms is like a piece of food item stuck between their teeth and preserved for millions of years,” said Dr Zeresenay Alemseged, from the California Academy of Sciences, co-author on two of the papers.

“Because feeding is the most important factor determining an organism’s physiology, behaviour and its interaction with the environment, these finds will give us new insight into the evolutionary mechanisms that shaped our evolution.”

It is not yet clear whether the change in diet included animals, but “the possible diets of some of our hominin kin” has been considerably narrowed down, Dr Matt Sponheimer, lead author of another of the papers, told BBC News.
A new habitat

“We now have good evidence that some early hominins began using plant foods that are not used in abundance by living African apes today, and this probably led to a major change in the way they used the landscape.

“One consequence could be that the dietary expansion led to a habitat expansion, as they could travel to more open habitats more efficiently.

“We know that many early hominins lived in areas that would not have readily supported chimpanzees with their strong preference for forest fruits. It could also be argued that this dietary expansion was a key element in hominin diversification.”

The study has also answered, at least in part, what researchers have long been speculating – how so many large species of primate managed to co-exist.

“They were not competing for the same foods,” said Prof Thure Cerling from the University of Utah, who led one of the research papers.

‘The modern human’

“All these species who were once in the human lineage, ventured out into this new world of foods 3.5 million years ago, but we don’t yet understand why that is.”

As well as looking at non-human primates, the researchers analysed fossils from other animals from the same era and did not find any evidence of a change in diet.

This combined research highlights a “step towards becoming the modern human”, said Dr Jonathan Wynn from the University of South Florida, who led the analysis of Australopithecus afarensis.

“Exploring new environments and testing new foods, ultimately might be correlated with further changes in human history.”

These four complementary studies give a persuasive account of shifts in dietary niche in East African hominins, Dr Louise Humphrey from the Natural History Museum in London, told BBC news.